Double-jaw friction-grip clamp.



F. THOMAS.

DOUBLE JAW FRICTION GRIP CLAMP.

APPLICATION FILED MAR. 14, 1910.

1,037,560, Patented Sept. 3, 1912.

2 SHEETSSHEET 1.

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DOUBLE JAW FRIGTION GRIP CLAMP. APPLIOATION FILED MAE.14, 1910.

1,037,560. Patented Sept. 3, 1912.

2 SHEETS-SHEET 2.

wii'nessas .[nvcrzior FREDERICK THOMAS, 0F TOO'IING, LONDON, ENGLAND.

DOUBLE-J AW FRICTION-GRIP CLAMP.

Specification of Letters Patent.

Application filed March 14, 1910.

Patented Sept. 3, 1912.

Serial No. 549,244.

To all whom it may concern.

Be it known that I, F REDERIOK THOMAS, a subject of the King of GreatBritain, residing at Tooting, London, England, have invented a certainnew and useful Improved Double-J aw Friction-Grip Clamp, of which thefollowing is a specification.

This invention relates to a clamp which is specially suited for use inconnection with diamond drilling, Artesianwell and other boringoperations for holding, lifting or lowering the rod sections, and isequally applicable for any other purpose where rods, bars, spindles,shafts, cables and the like require to be held, lifted, lowered orhauled. It is also especially suitable for use when raising or loweringthe stamps of stamp mills and such like purposes. A It has heretoforebeen proposed to provide a wire grip for use in connection with meansfor straining or stretching wire, and which is adapted to grasp the wirewlth a grip proportional to the pull, said wire grip comprisingpermanently pivoted jaws, and links permanently pivoted to each jaw andto a member which is connected to the straining device. but under myinvention the clamp consists of two jaws of special shape, and which areremovably jointed together in such manner that they completely surroundthe object being operated on and,

on the weight being thrown upon them or a pull being exerted on them,they automatically grasp theobject and hold it fast with a tightfrictional grip proportional to the weight or pull.

In order that my said invention may be clearly understood I have shownon the accompanying drawings, by way of example, some forms ofconstruction and various applications in connection with engineerln'gand m1n1ng work.

Figures 1 and 2 show, in side elevation the "like from slipping down theborehole during the connectionor disconnection-of the sections. Y

Referring to the drawings whereon; the same reference letters whereverrepeatedin; dicate the same parts, the clamp'consists of two jaws a, Z),of special shape, as shown on the drawings, and which are removablyjointed together by pins and eyes or hooks.

Each jaw has two internal faces, as shown in dotted lines ate, 1, at" anangle to one another and holes 9 are made in each jaw for the receptionof pins or'bolts h. The construction of the clamp is such thatwhen theweightof the objectbeing operated on is thrown upon the jaws a, b, or apull is exerted on them they automatically grasp the object and hold itfast with a tight frictional grip which is proportional to the weight orpull.

In Figs. 1 and 2 the clamp is shown. w th the jaw a having externallyprojecting pins 0, 0, while thejaw 79 has corresponding books (Z, (Z, sothat the aws can be readily connected and disconnected at any'part of arod, shaft, or cable as the case may be. Of course, if so desired, thejaw b may have internally projecting pins and the jawa have hooks.

In the case of the hand clamp shown at Figs. 3 and 4c each jaw a, b, isprovided with a handle m. Fig. 4 shows the jaws of the clamp beingfitted around the rod o and caused to engage, while Fig. 3 shows thejaws engaged and gripping the rod 12 so that the same can be raisedorlifted by the handles m, m. j I p In the arrangement shown at Fig. 5for lifting, lowering or handling stamp battery stems the two jaws a andb of the clamp are attached to the traveling chain block by chains androds and shacklesi, j. When it is required to lift the stamp stenr B,the clamp is brought over the stem B and the jaws a and 6 connected inthemanner shown at the left hand of the figure for the stamp stem A.When connected, as shown, the up ward pull of the chain block will causethe clamp to grip and raise the stem to the desired position and, beinghung in a linewith the center of the stem, the said stem can be revolvedto any desired position fordriving the tappet keys or'for driving offthe head or shoe and held in that position by the suspension clamp Csuspended by shackles and chain links Z from the upperguide D,whereuponthe chain block and its clamp can be passed on to other stems orbatteries. When the tappet keys are driven'home or the new head or shoeplaced in position to receive the stem the clamp C may be released by asmart upward tap of a hammer and left sus pended clear of the stems asshown at the left hand side of the figure. The guide D is provided withhooks k for each stem so that the suspension clamp C may be shifted fromone stem to another thereby enabling one clamp C to be used for everyfive stamps. This invention obviates the necessity of climbing on to theupper guide to place a lifting ring over the stems each time a stem hasto be lifted and likewise the necessity for climbing up to release thesaid ring.

In Figs. 6 and 7 the clamp is shown with a supporting frame 00 and theaws have laterally projecting journals 3 y, carried in bearings 92 insuch a manner as to swivel in the framework at being retained within thebearings by levers 0 pivoted at 79 and secured by cotters g, thusallowing the clamp to adjust itself and its operations to any angle ofthe drill rod. The clamp is shown as provided with removable metalliners a, 10 these reducing liners being made of a metal or substancesuitable to the article to be gripped. By removing the cotters q andraising the pivoted levers 0 the clamp may be readily removed from itsbearings, the framework 00 being open at one end facilitating itsremoval from the rod when desired. In these figures is also shown meanswhereby the clamp may be held open for a time, as when lowering drillrods, thereby obviating the necessity for removing the clamp. The jawsof the clamp are raised and supported by a forked foot lever 1", 1"having lateral project-ions s, s, which can be fitted in open slots s 8in a block av on the framework thereby forming a fulcrum. This lever,which can also be operated by hand, if so desired, by fitting a bar a(as shown in Fig. 6) into the hole 1 of the lever, is held in positionby a loose pin '6. When the drill rods are lowered for another rodsection to be screwed on, the loose pin t is removed and the weight ofthe rods causes the clamp to automatically grip until the weight isagain taken by the hoist when the clamp is released whereupon it can beraised and opened by the foot lever and the loose pin be again insertedto hold the clamp in that position. It will be obvious that with a shortfoot lever and with the weight of the rods on the clamp it cannot beopened. until the weight of the rods is taken by the hoist so that anypossibility of accidental release is absolutely avoided. The rods may behoisted and lowered by means of the usual eye bolt but, preferably, by aclamp as shown in Figs. 1 and 2, which, being con-- nected to thehoisting rope, will grip and raise or lower the rods as beforedescribed. When the rods are being lifted the ground clamp Fig. 7automatically opens sufficiently for the rods to pass through and whenhoisted up and the hoisting rope slackened it likewise automaticallygrips the same rods so that on the weight being removed from the hoistthe lifting clamp may be detached and lowered for the nextsection.Should the rope break, when hoisting, the ground clamp likewiseimmediately grips the rods.

If desired, instead of both pins 0 being formed on one jaw and bothhooks (Z on the other jaw, the jaws may each be correspondingly formedwith a pin 0 on one side thereof and a hook (Z on the other side thereofso that the jaws may engage in a similar manner, the one with the other.

Having now fully described my invention what I claim and desire tosecure by Letters Patent is 1. A clamp comprising two separate jaws ofcurved formation each jaw having an upper internal face and a lowerinternal face arranged at an angle to one another the upper internalfaces of both jaws constituting vertically parallel gripping surfaceswhen in contact with the object to be held and means for removablyjointing the jaws to gether comprising pins projecting from the jaws andhooks on the jaws for engagement with the pins, the hooks having theiropenings at the upper sides thereof so that the jaws may be caused togrip or release the object to be held without danger of becomingaccidentally detached.

2. A clamp comprising two separate jaws of curved formation each jawhaving an upper internal face and a lower internal face arranged at anangle to one another the upper internal faces of both jaws constitutingvertically parallel gripping surfaces when in contact with the object tobe held and means for removably jointing the jaws together comprising apair of pins projecting from one of the jaws and a pair of hooks on theother jaw for engagement with the pins, the hooks having their openingsat the upper sides thereof so that the jaws may be caused to grip or.release the object to be held without danger of becoming accidentallydetached.

3. A clamp comprising two separate jaws of curved formation each jawhaving an upper internal face and a lower internal face arranged at anangle to one another the upper internal faces of both aws constitutingverticallyparallel gripping surfaces when in contact with the object tobe held, removable liners for the jaws, and means for removably jointingthe jaws together comprising pins projecting from the jaws and hooks onthe jaws for engagement with the pins, the hooks having their openingsat the upper sides thereof so that the jaws may be caused to grip orrelease the object to be held without danger of becoming accidentallydetached.

4. A clamp comprising two separate aws of curved formation each jawhaving an upper internal face and a lower internal face arranged at anangle to one another the upper internal faces of both jaws constitutingvertically parallel gripping surfaces when in contact with the object tobe held, journals on the aws, a framework, swivel bearings in theframework for said journals, and means for removably ointing the jawstogether comprising pins projecting from the jaws and hooks on the jawsfor engagement with the pins, the hooks having their openings at theupper sides thereof so that the jaws may be caused to grip or releasethe object to be held without danger of becoming accidentally detached.

5. A clamp comprising two separate jaws removahly jointed together eachjaw having an angled internal surface, journals on the jaws, aframe-work, swivel hearings in the frame-work, means for holding thejournals in the frame-work and means for retaining the jaws in the openposition when so desired.

6. A clamp comprising two separate jaws removably jointed together eachjaw having an angled internal surface, journals on the jaws, aframe-work, swivel hearings in FREDERICK THOMAS.

-Witnesses:

G. HELYER, Gr. ST. GEM.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D; G.

